A liquid crystal beam deflection device and its driving method

Abstract

The application relates to a liquid crystal light beam deflection device and a driving method thereof, which comprises a first glass substrate, a first transparent conductive layer, a first orientation layer, a liquid crystal layer, a second orientation layer, a second transparent conductive layer and a second glass substrate which are sequentially arranged in layers from top to bottom, at least one transparent conductive layer of the first transparent conductive layer and the second transparent conductive layer is connected with a driving electrode, each driving electrode is respectively connected to a mutually independent voltage source to apply different voltages, and the other transparent conductive layer is connected to a reference potential or a ground terminal. Compared with the prior art, the application applies voltages through a plurality of independent driving electrodes arranged in the peripheral area of the transparent conductive layer, forms a controllable two-dimensional electric field distribution in the liquid crystal layer, adjusts the liquid crystal orientation, the optical phase distribution and the light beam propagation direction, reduces the number of electrodes and the driving channels, and improves the two-dimensional phase regulation capability of the liquid crystal device.

Description

Technical Field

[0001] This invention relates to the field of liquid crystal phase modulators, and in particular to a liquid crystal beam deflection device and its driving method. Background Technology

[0002] Liquid crystal materials combine the fluidity of liquids with the anisotropy of crystals. Their molecular orientation can be controllably changed under an applied electric field, leading to alterations in optical properties such as effective refractive index and phase retardation. Therefore, liquid crystal materials are commonly used in phase modulation devices such as spatial light modulation.

[0003] In applications such as optical communication, optical switching, free-space optical coupling, fiber collimation coupling, and precision optical assembly, the optical beam often experiences small-angle deflections or lateral shifts due to mechanical assembly errors, temperature drift, vibration disturbances, or changes in system attitude. This leads to deterioration in mode matching between the outgoing beam and the receiving fiber endface, collimating lens, or target optical channel. To compensate for these deviations, adjustable phase distribution or two-dimensional wavefront modulation devices need to be introduced into the optical path. This allows the outgoing beam to undergo minute angle corrections, pointing adjustments, or wavefront compensation in the lateral two-dimensional direction, thereby improving fiber coupling efficiency.

[0004] Existing phase modulation devices mostly employ sandwich structures such as parallel plate electrodes, primarily generating an electric field along the thickness direction of the liquid crystal layer to modulate the tilt angle of liquid crystal molecules and optical phase delay. To achieve lateral phase gradients, common solutions include pixel electrodes, coupled with complex driving circuits, to create different voltage distributions in the lateral direction of the device. However, pixel array electrodes suffer from structural complexity, numerous driving channels, difficult routing, discontinuous edge electric fields, high manufacturing costs, and low transmittance due to reduced effective aperture caused by electrode gaps, driving traces, and switching elements, hindering miniaturization, low cost, and high reliability beam correction applications. Furthermore, while using two-end electrodes can create a one-dimensional voltage gradient, it is mainly suitable for phase modulation in a single direction, with limited capabilities for two-dimensional phase distributions, arbitrary beam deflection, or composite wavefront modulation.

[0005] Existing patent CN208999731U discloses a liquid crystal phase modulator that divides the electrodes on each substrate of the liquid crystal phase modulator into multiple electrode patterns. Although this modulator improves the response speed of the liquid crystal phase modulator, it cannot be applied to two-dimensional phase modulation and beam deflection.

[0006] Therefore, it is necessary to provide a liquid crystal beam deflection device with a simple structure, fewer driving channels, small spatial volume, and the ability to achieve two-dimensional liquid crystal orientation control and optical phase modulation with a small amount of electrode voltage. Summary of the Invention

[0007] The purpose of this invention is to overcome the problems of complex structure, discontinuous edge electric field, low transmittance, and difficulty in achieving two-dimensional phase modulation and arbitrary beam deflection by simple two-end electrodes in existing phase modulation devices. The invention provides a liquid crystal beam deflection device and its driving method, which improves the two-dimensional phase modulation capability of the liquid crystal device while reducing the number of electrodes and driving channels. It solves the problems of complex structure, cumbersome driving method, discontinuous phase distribution, and insufficient degree of freedom of control in existing liquid crystal beam deflection devices.

[0008] The objective of this invention can be achieved through the following technical solutions: A liquid crystal beam deflection device includes, from top to bottom, a first glass substrate, a first transparent conductive layer, a first alignment layer, a liquid crystal layer, a second alignment layer, a second transparent conductive layer, and a second glass substrate arranged in layers. At least one of the first and second transparent conductive layers is connected to a driving electrode. Each driving electrode is connected to an independent voltage source to apply different voltages. The other transparent conductive layer is connected to a reference potential or a ground terminal.

[0009] Furthermore, the driving electrode is disposed in a non-light-transmitting area or its adjacent area outside the effective light-transmitting aperture; the non-light-transmitting area includes one or more of the following: the transparent conductive layer edge area, the substrate edge area, the encapsulation frame adhesive area, the light-shielding area, and the device sidewall area.

[0010] Furthermore, the driving electrode is one or more of the following: corner electrode, edge electrode, and multi-segment edge electrode.

[0011] Furthermore, the friction directions of the first orientation layer and the second orientation layer are parallel.

[0012] Furthermore, the transparent conductive layer is a transparent conductive film with high sheet resistance.

[0013] Furthermore, a high-resistivity layer or a resistance-regulating layer is provided between the transparent conductive layer and the driving electrode, between the transparent conductive layer and the alignment layer, or in a local / overall area of ​​the transparent conductive layer.

[0014] Furthermore, the high-resistivity layer is made of materials including transparent conductive oxides, conductive polymers, carbon-based materials, metal-based materials, or composite materials.

[0015] Furthermore, the reference potential is a fixed potential, a time-varying potential, an AC potential, a reference potential in differential driving, or a reference potential formed by circuit equivalence.

[0016] The present invention also provides a driving method for the liquid crystal beam deflection device as described above, wherein the magnitude, polarity and relative difference of the voltage of each driving electrode are changed, and the direction and amplitude of the phase gradient are adjusted, thereby controlling the deflection direction and deflection angle of the emitted beam.

[0017] Furthermore, the polarization direction of the incident light matches the initial alignment direction or effective modulation direction of the liquid crystal in the liquid crystal beam deflection device. Compared with the prior art, the present invention has the following beneficial effects: 1. The present invention has driving electrodes connected in the transparent conductive layer, which can form a two-dimensional potential distribution between the common electrode and only a few driving electrodes. Compared with pixel array electrodes, it has a simple structure, fewer driving channels, and smaller volume.

[0018] 2. In this invention, each driving electrode is connected to an independent voltage source, and phase gradients of different directions and intensities can be achieved by adjusting the voltage of the driving electrodes.

[0019] 3. By changing the magnitude, polarity, and relative difference of the voltages of each driving electrode, this invention can adjust the direction and amplitude of the phase gradient, thereby realizing electrically controlled beam deflection, wavefront modulation, or adjustable liquid crystal prism functions, which can improve the coupling efficiency of optical fibers in applications such as optical communication and optical switching.

[0020] 4. The transparent conductive layer of the present invention uses a transparent conductive film with high sheet resistance or sets a high resistance layer or a resistance control layer, which helps to form a smooth potential distribution and reduce phase abrupt changes.

[0021] 5. This invention is suitable for liquid crystal optical devices with millimeter or micrometer apertures and is compatible with existing liquid crystal cell manufacturing processes. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the structure of the present invention; Figure 2 This is a schematic diagram illustrating a feasible driving electrode configuration for the present invention. Figure 3 A schematic diagram of two-dimensional beam deflection applying the present invention; Figure 4 The effect of beam deflection in one dimension when the equivalent refractive index of liquid crystal changes linearly. Figure 5 Potential and electric field distribution within a high sheet resistance transparent conductive film (ITO) when the driving electrodes are positioned at the four corners of the edge of the transparent conductive layer; Figure 6 This describes the potential and electric field distribution within a high sheet resistance transparent conductive film (ITO) when the driving electrodes are positioned on the four edges of the substrate. Detailed Implementation

[0023] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments. These embodiments are implemented based on the technical solution of the present invention, providing detailed implementation methods and specific operating procedures. However, the scope of protection of the present invention is not limited to the following embodiments.

[0024] Example 1 This embodiment provides a liquid crystal beam deflection device, which adopts a sandwich structure, such as... Figure 1 As shown, the substrate includes, from top to bottom, a first glass substrate 1, a first transparent conductive layer 2, a first alignment layer 3, a liquid crystal layer 4, a second alignment layer 5, a second transparent conductive layer 6, and a second glass substrate 7, arranged in layers. At least one of the first transparent conductive layers 2 and the second transparent conductive layer 6 is connected to a driving electrode 8. Figure 2 As shown, each driving electrode is connected to an independent voltage source to apply different voltages, and another transparent conductive layer is connected to a reference potential or ground. By applying adjustable voltages to each driving electrode, in conjunction with a common electrode, a two-dimensional potential distribution and a spatially distributed electric field are formed within the transparent conductive layer and the liquid crystal layer. This allows for the manipulation of the liquid crystal molecule orientation, equivalent refractive index distribution, and optical phase distribution, thereby achieving two-dimensional beam deflection, wavefront modulation, or fiber coupling correction, such as... Figure 3 As shown in the figure. This scheme improves the two-dimensional phase modulation capability of liquid crystal devices while reducing the number of electrodes and driving channels, and solves the problems of complex structure, cumbersome driving method, discontinuous phase distribution and insufficient degree of freedom of existing liquid crystal beam deflection devices.

[0025] Furthermore, a transparent conductive layer is attached to the inner side of the glass substrate. The transparent conductive layer is continuous or substantially continuous at least within the effective light-transmitting area; its peripheral area may be continuous, segmented, patterned, slotted, partially interrupted, or have non-uniform surface resistance.

[0026] Specifically, in this embodiment, the driving electrode is deposited in the peripheral area of ​​the first transparent conductive layer 2, i.e. the upper transparent conductive layer. The driving electrode is a metal driving electrode. Each driving electrode is led out through a wire and connected to an independent voltage source so as to apply different driving voltages.

[0027] Furthermore, the surrounding area includes a non-light-transmitting area outside the effective light-transmitting aperture or its adjacent area, wherein the non-light-transmitting area includes, but is not limited to, one or more of the following: the transparent conductive layer edge area, the substrate edge area, the encapsulation frame adhesive area, the light-shielding area, and the device sidewall area.

[0028] Specifically, refer to Figure 2 As shown, the driving electrode can be one or a combination of corner electrodes, edge electrodes, and multi-segment edge electrodes.

[0029] Specifically, in this embodiment, the second transparent conductive layer 6, i.e. the lower transparent conductive layer, serves as a common electrode and is connected to the reference potential or ground terminal via a wire.

[0030] Furthermore, the reference potential can be a fixed potential, a time-varying potential, an AC potential, a reference potential in differential drive, or a reference potential formed by circuit equivalence.

[0031] Furthermore, the two alignment layers are rubbed in parallel directions and are attached between the liquid crystal layer and the transparent conductive layer to define the initial alignment direction of the liquid crystal molecules. The liquid crystal layer is located at the center of the device, filling the space between the upper and lower alignment layers, and generates a spatially distributed electric field under the combined action of the upper and lower transparent conductive layers, thereby achieving electronically controlled adjustment of the liquid crystal molecule alignment and optical phase distribution.

[0032] In some embodiments, the transparent conductive layer may be a transparent conductive film with high sheet resistance, or a high-resistivity layer or resistance modulation layer may be added between the transparent conductive layer and the driving electrode, between the transparent conductive layer and the alignment layer, or in a local / overall area of ​​the transparent conductive layer.

[0033] In specific embodiments, transparent conductive film materials that can be used as high sheet resistance include, but are not limited to: indium tin oxide (ITO), indium zinc oxide (IZO), aluminum-doped zinc oxide (AZO), and transparent conductive polymers (such as poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) PEDOT:PSS). In this embodiment, indium tin oxide (ITO) is used.

[0034] Specifically, the high-resistivity layer can be formed from conductive oxides such as high sheet resistance ITO, IZO, and AZO, conductive polymers, graphene, thin metal oxide layers, or other materials with in-plane resistance characteristics. By setting a high-resistivity layer, the voltage applied by the peripheral driving electrodes can produce a continuous or near-continuous potential transition in the transverse plane of the device, thereby forming a smoother and more designable two-dimensional potential distribution.

[0035] The working principle of the above-mentioned liquid crystal beam deflection device is as follows: A two-dimensional potential distribution is formed within the upper transparent conductive layer by conductive electrodes. And establish a spatially distributed electric field between it and the ground terminal or common terminal of the lower transparent conductive layer. Liquid crystal molecules exhibit dielectric anisotropy and undergo orientation shift under the influence of an electric field. Since liquid crystal materials also possess optical anisotropy, when light is incident, the change in the orientation of the liquid crystal molecules alters the equivalent refractive index, thereby changing the optical path difference and the exit phase of the incident light. One-dimensional beam manipulation scenarios include... Figure 4 As shown.

[0036] The equivalent refractive index of a liquid crystal is related to the orientation of its molecules. For uniaxial anisotropic liquid crystals, the ordinary optical refractive index can be used. Non-ordinary optical refractive index Describe its optical properties. Under certain polarization and propagation conditions, the liquid crystal alignment angle... The corresponding equivalent refractive index can be approximated as: in, This represents the angle between the orientation of the liquid crystal molecules and the reference direction. As the applied electric field changes the orientation of the liquid crystal molecules, The device's lateral position changes, thus causing Spatial changes occur.

[0037] For a thickness of The liquid crystal layer, when the equivalent refractive index of the liquid crystal at a certain lateral position is... When light passes through this position, the optical path length can be expressed as: If within the effective aperture Within this range, the effective refractive index variation that a liquid crystal can achieve is: The maximum phase modulation depth that the liquid crystal layer can provide is: in, This is the operating wavelength.

[0038] When different voltages are applied to the electrodes, a non-uniform potential distribution forms in the upper transparent conductive layer, causing different electric field intensities at different lateral positions within the liquid crystal layer. Liquid crystal molecules at different positions undergo varying degrees of deflection, resulting in a spatially distributed equivalent refractive index. After incident light passes through the liquid crystal layer, different positions acquire different optical path differences, thus forming a spatially varying phase distribution. If this phase distribution changes approximately linearly in a certain lateral direction... If the effective aperture width along the phase gradient direction Total optical path difference generated internally Then the outgoing wavefront is equivalent to being tilted, and its deflection angle is... It can be approximately satisfied as follows: From the perspective of phase gradient, it can be expressed as: Therefore, the deflection capability of the device is mainly determined by the liquid crystal thickness, the adjustable equivalent refractive index range of the liquid crystal, and the effective aperture. The role of the electrodes is to form a controllable two-dimensional electric field distribution in the lateral plane of the liquid crystal layer through a small amount of independent voltage, thereby adjusting the liquid crystal orientation, equivalent refractive index, optical path difference, and phase gradient, and ultimately achieving beam deflection in one-dimensional or two-dimensional directions.

[0039] The driving method for the above-mentioned liquid crystal beam deflection device is as follows: The metal driving electrodes of the upper transparent conductive layer are connected to independent voltage sources, while the lower transparent conductive layer is connected to a common potential or ground. During operation, by adjusting the voltages of the different driving electrodes, a two-dimensional potential distribution determined by different voltage values ​​is formed within the upper transparent conductive layer, creating a spatially distributed electric field between it and the ground terminal of the lower transparent conductive layer. Under the influence of this electric field, the liquid crystal molecules undergo varying degrees of orientation changes, resulting in a continuously changing equivalent refractive index and phase distribution within the transverse plane of the device.

[0040] When the same or nearly the same voltage is applied to the peripheral driving electrodes located on the same side or in the same direction, while a different voltage is applied to the peripheral driving electrodes on the opposite side or in another direction, an approximately one-dimensional potential gradient can be formed in the lateral direction of the device, which can be used to achieve beam deflection in a single direction. When different voltages are applied to multiple peripheral driving electrodes, a two-dimensional potential distribution can be formed in the upper transparent conductive layer and the liquid crystal layer, which can be used to achieve two-dimensional phase modulation, beam deflection in any lateral direction, or composite wavefront modulation. By changing the magnitude, polarity, and relative difference of the voltages of each peripheral driving electrode, the direction and amplitude of the phase gradient can be adjusted, thereby controlling the deflection direction and deflection angle of the emitted beam.

[0041] The incident light polarization requirements for the aforementioned liquid crystal beam deflection device are as follows: Optical phase modulation mainly comes from the coupling between the polarization direction of the incident light and the director of the liquid crystal molecules. The polarization direction of the incident light is preferably matched with the initial orientation direction or effective modulation direction of the liquid crystal.

[0042] When the electric field polarization direction of the incident light is parallel to the orientation direction of the liquid crystal molecules, the light mainly experiences the anomalous optical equivalent refractive index that varies with voltage. The liquid crystal orientation change caused by the four-corner voltage can be converted into a spatially varying phase delay, thereby achieving a larger phase modulation depth and beam deflection.

[0043] When the polarization direction of the incident light does not match the initial alignment direction of the liquid crystal, a polarizer can be placed in front of the device to make the incident light linearly polarized to match the alignment direction of the liquid crystal; alternatively, depending on the system requirements, the polarization direction can be made consistent with the target phase modulation direction by adjusting the rubbing direction of the alignment layer, the initial alignment direction of the liquid crystal, or the incident polarization direction.

[0044] In this embodiment, the liquid crystal beam deflection device adopts a transmission structure, with the driving electrodes plated at the four corners of the upper transparent conductive layer. The effective aperture of the device is 5mm × 5mm, and the thickness of the liquid crystal layer is 10μm. Nematic liquid crystal is selected as the liquid crystal material, and its ordinary light refractive index is [not specified]. The anomalous optical refractive index is 1.50. The birefringence difference is 1.70. The transparent conductive layer uses an ITO conductive film with a sheet resistance of 400 Ω / sq to create a smooth potential distribution between the four corner electrodes. The four corner metal driving electrodes are square electrode sheets with a size of 1 mm × 1 mm.

[0045] During operation, apply the same or approximately the same low voltage to the two corner drive electrodes on the left side of the device, and apply the same or approximately the same high voltage to the two corner drive electrodes on the right side of the device. The drive voltage is an AC voltage with a frequency of 1kHz. Apply an effective value of 2V to the upper left and lower left corner electrodes, and apply an effective value of 4V to the upper right and lower right corner electrodes. Connect the lower ITO electrode layer to the common potential or ground.

[0046] Under the aforementioned voltage, the upper transparent conductive layer forms an approximately continuously varying potential distribution in the left-right direction, creating a spatially distributed electric field between it and the lower ITO common electrode. Liquid crystal molecules at different lateral positions are subjected to different electric fields, resulting in varying degrees of orientation deflection, causing the equivalent refractive index of the liquid crystal layer to continuously change along the x-direction. After incident light passes through the liquid crystal layer, it acquires an approximately linear optical path difference and phase distribution in the x-direction, forming an equivalent phase wedge, thereby deflecting the outgoing light beam along the x-direction.

[0047] With an operating wavelength λ=1550nm, and a liquid crystal layer thickness of 10μm, the achievable effective refractive index change is... When the value is approximately 0.155, the optical path difference can be obtained as follows: The theoretical small-angle deflection is approximately: Figure 5 When the driving electrodes are positioned at the four corners of the transparent conductive layer, the potential and electric field distributions within the high sheet resistance transparent conductive film (ITO) are shown. The upper diagram illustrates a symmetrical voltage setting, enabling one-dimensional beam deflection, while the lower diagram shows an asymmetrical voltage setting, enabling two-dimensional beam deflection. By applying different voltages to multiple peripheral driving electrodes, continuous or near-continuous two-dimensional potential and spatial electric field distributions can be formed within the transparent conductive layer and the effective light-transmitting area. This provides an electrical basis for liquid crystal alignment control, phase gradient formation, and beam deflection.

[0048] Example 2 This embodiment provides a liquid crystal beam deflection device that drives beam deflection through a two-dimensional phase distribution achieved by four-sided electrodes.

[0049] Specifically, in this embodiment, driving electrodes are plated on the four sides of the upper transparent conductive layer. Different voltages are applied to the driving electrodes, and the voltages on the four sides together determine the two-dimensional potential distribution in the transparent conductive layer. Unlike the potential gradient in Embodiment 1, which mainly changes along a single direction, this embodiment can simultaneously generate potential changes in the x and y directions, so that the electric field intensity in the liquid crystal layer is distributed in a two-dimensional space in the transverse plane.

[0050] Liquid crystal molecules adopt different orientation states based on the local electric field distribution, thus forming a two-dimensional equivalent refractive index distribution within the liquid crystal layer. Incident light, after passing through the liquid crystal layer, acquires a two-dimensional optical path difference and a two-dimensional phase distribution. By rationally setting the voltage combination of the four electrodes, the phase gradient can be directed in any lateral direction, thereby achieving beam deflection in any direction; it can also form a composite phase distribution with a non-linear gradient, used for wavefront shaping, two-dimensional scanning, aberration compensation, or composite wavefront modulation. The amplitudes and relative relationships of the four voltages can be preset, look up in a table, or adjusted in a closed loop according to the target deflection direction, deflection angle, or target wavefront shape.

[0051] Figure 6 When the driving electrodes are positioned on the four edges of the transparent conductive layer, the potential and electric field distributions within the high sheet resistance transparent conductive film (ITO) are shown. The upper diagram illustrates a symmetrical voltage setting, enabling one-dimensional beam deflection, while the lower diagram shows an asymmetrical voltage setting, enabling two-dimensional beam deflection. By applying different voltages to multiple peripheral driving electrodes, continuous or near-continuous two-dimensional potential and spatial electric field distributions can be formed within the transparent conductive layer and the effective light-transmitting area. This provides an electrical basis for liquid crystal alignment control, phase gradient formation, and beam deflection.

[0052] The rest is the same as in Example 1.

[0053] Example 3 This embodiment provides a liquid crystal beam deflection device that achieves fiber-coupled deflection correction through multiple edge electrodes.

[0054] Specifically, in this embodiment, the multi-segment edge electrode driven liquid crystal beam deflection device of the present invention is disposed in the optical fiber coupling optical path, for example, between the collimating fiber and the receiving fiber, between the collimating lens and the fiber end face, or between the free space optical communication receiving end and the optical fiber coupling end. In the optical communication system, due to mechanical assembly errors, temperature drift, vibration disturbances, platform attitude changes, or free space transmission disturbances, the incident beam may be deflected at a small angle or laterally offset relative to the receiving fiber end face, causing the beam spot to not coincide well with the receiving fiber mode, thereby reducing the coupling efficiency.

[0055] During operation, the voltage combination of each edge electrode segment can be adjusted based on the coupled optical power, spot position, or feedback error signal monitored at the receiving end. This creates a phase gradient within the liquid crystal layer that is opposite to the original beam deflection direction. This phase gradient causes a compensatory deflection of the beam passing through the device, thereby correcting the original beam's incident angle error or pointing error, and re-aligning the outgoing beam with the receiving fiber end face or the target position of the receiving optical system. By continuously adjusting the voltage amplitude and phase of different edge electrode segments, dynamic compensation for small-angle deflections of different directions and amplitudes can be achieved.

[0056] Because the device of this invention can form a two-dimensional adjustable phase gradient with a small number of electrodes, fine-tuning of the beam angle can be achieved without employing complex mechanical adjustment mechanisms. This embodiment can be used in fiber optic communication, free-space optical communication, laser collimation coupling, optical switching, optical switching, or precision optical assembly systems to improve the overlap between the beam and the receiving fiber mode, reduce coupling loss, and enhance the system's stability under conditions of vibration, thermal drift, or assembly errors.

[0057] The rest is the same as in Example 1.

[0058] Example 4 This embodiment provides a liquid crystal beam deflection device, which adopts a combination electrode structure of corner and edge.

[0059] In this embodiment, corner driving electrodes and edge driving electrodes are simultaneously disposed in the peripheral region of the transparent conductive layer of the liquid crystal beam control device. The corner driving electrodes can be respectively disposed in the four corner regions of the transparent conductive layer, and the edge driving electrodes can be disposed in the upper edge, lower edge, left edge, and / or right edge regions of the transparent conductive layer. The edge driving electrodes can be continuous strip electrodes or divided into multiple independent electrode segments along the edge direction. Each corner driving electrode and each edge driving electrode is connected to an independent driving voltage source via a wire, thereby forming a peripheral electrode structure in which the corners and edges jointly participate in the control.

[0060] During operation, the voltage combinations of the corner driving electrodes and the edge driving electrodes can be adjusted according to the deflection direction, deflection angle, or wavefront shape of the target beam. The corner driving electrodes can be used to establish diagonal, oblique, or two-dimensional asymmetric potential distributions in the device, while the edge driving electrodes can be used to enhance the potential gradient along the horizontal or vertical direction, and also to correct local electric field inhomogeneities caused by the corner electrodes. By combining the corner and edge electrodes, a more flexible two-dimensional potential distribution and spatial electric field distribution can be formed in the transparent conductive layer and liquid crystal layer, allowing for controllable changes in the liquid crystal molecule orientation, equivalent refractive index, and optical phase in the transverse plane.

[0061] Compared to structures using only corner electrodes or only edge electrodes, the combined corner and edge electrode structure offers more degrees of freedom in voltage regulation, which is beneficial for improving the accuracy of phase gradient direction control, expanding the adjustable deflection range, and improving the uniformity or linearity of phase distribution within the effective aperture. This structure can be used in scenarios such as two-dimensional beam deflection, adjustable liquid crystal prisms, wavefront shaping, aberration compensation, fiber coupling efficiency optimization, and pointing error correction in free-space optical communication.

[0062] The rest is the same as in Example 1.

[0063] Example 5 This embodiment provides a liquid crystal beam deflection device, wherein a first transparent conductive layer and a second transparent conductive layer are disposed opposite to each other, and both the first transparent conductive layer and the second transparent conductive layer are connected to at least one driving electrode.

[0064] When both the first and second transparent conductive layers are connected to at least one driving electrode, the electric field in the liquid crystal layer is jointly determined by the potential distributions on the two transparent conductive layers. Let the potential of the first transparent conductive layer at the lateral position be... The potential of the second transparent conductive layer at the corresponding position is Therefore, the local electric field along the thickness direction of the liquid crystal layer is mainly related to the potential difference between the two. Relatedly, by adjusting the driving electrode voltages on the two transparent conductive layers respectively, a spatially varying potential difference distribution and electric field distribution can be formed within the liquid crystal layer. This causes liquid crystal molecules at different lateral positions to undergo varying degrees of orientation changes, thereby forming a spatially varying equivalent refractive index distribution and phase distribution. The gradient of this phase distribution can deflect or modulate the light beam passing through the liquid crystal layer.

[0065] Compared to the method of connecting multiple driving electrodes with only one transparent conductive layer and using another transparent conductive layer as a common electrode, when both transparent conductive layers participate in the driving, the local electric field gradient can be enhanced or weakened by differential control of the potential distribution of the upper and lower electrodes, thereby increasing the degree of freedom in controlling the two-dimensional electric field distribution and phase distribution.

[0066] The rest is the same as in Example 1.

[0067] The preferred embodiments of the present invention have been described in detail above. It should be understood that those skilled in the art can make numerous modifications and variations based on the concept of the present invention without creative effort. Therefore, all technical solutions that can be obtained by those skilled in the art based on the concept of the present invention through logical analysis, reasoning, or limited experimentation on the basis of existing technology should be within the scope of protection defined by the claims.

Claims

1. A liquid crystal beam deflection device, characterized in that, The system comprises, from top to bottom, a first glass substrate, a first transparent conductive layer, a first alignment layer, a liquid crystal layer, a second alignment layer, a second transparent conductive layer, and a second glass substrate arranged in layers. At least one of the first and second transparent conductive layers is connected to a driving electrode. Each driving electrode is connected to an independent voltage source to apply different voltages. The other transparent conductive layer is connected to a reference potential or a ground terminal.

2. The liquid crystal beam deflection device according to claim 1, characterized in that, The driving electrode is disposed in a non-light-transmitting area or its adjacent area outside the effective light-transmitting aperture; the non-light-transmitting area includes one or more of the following: the transparent conductive layer edge area, the substrate edge area, the encapsulation frame adhesive area, the light-shielding area, and the device sidewall area.

3. The liquid crystal beam deflection device according to claim 2, characterized in that, The driving electrode is one or more of the following: corner electrode, edge electrode, and multi-segment edge electrode.

4. The liquid crystal beam deflection device according to claim 1, characterized in that, The friction directions of the first orientation layer and the second orientation layer are parallel.

5. The liquid crystal beam deflection device according to claim 1, characterized in that, The transparent conductive layer is a transparent conductive film with high sheet resistance.

6. The liquid crystal beam deflection device according to claim 1, characterized in that, A high-resistivity layer or a resistance-regulating layer is disposed between the transparent conductive layer and the driving electrode, between the transparent conductive layer and the alignment layer, or in a local / overall area of ​​the transparent conductive layer.

7. The liquid crystal beam deflection device according to claim 6, characterized in that, The high-resistivity layer is made of materials including transparent conductive oxides, conductive polymers, carbon-based materials, metal-based materials, or composite materials.

8. The liquid crystal beam deflection device according to claim 1, characterized in that, The reference potential is a fixed potential, a time-varying potential, an AC potential, a reference potential in differential driving, or a reference potential formed by circuit equivalence.

9. A driving method for the liquid crystal beam deflection device as described in claim 1, characterized in that, By changing the magnitude, polarity, and relative difference of the voltages of each driving electrode, the direction and amplitude of the phase gradient are adjusted, thereby controlling the deflection direction and deflection angle of the emitted beam.

10. The driving method according to claim 9, characterized in that, The polarization direction of the incident light matches the initial orientation direction or effective modulation direction of the liquid crystal in the liquid crystal beam deflection device.

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